The present invention relates to acoustical panels and more particularly to an acoustical panel suitable for use in facilities which require a high degree of sanitary control. Such facilities include food processing plants, bottling and beverage plants, dairies, bakeries, meat and poultry plants, pharmaceutical and medical equipment facilities as well as electronic component and semiconductor manufacturing facilities. It is well known that people who work in facilities of the type described above are exposed routinely to hazardous noise levels. Past efforts to effectively control noise levels in such facilities have been thwarted to a large extent because conventional acoustical materials are either not sufficiently durable to permit their use in an industrial environment or not able to meet the sanitary requirements for such plants. In addition, the walls, floors and ceilings of such facilities must be smooth and hard for easy cleaning. Such surfaces raise the ambient noise levels generated by machinery and the like through the reflection of the sound waves generated in the plant.
Several types of easily cleaned acoustical panels which have proven to be useful to control sound emissions are described in applicant's co-pending U.S. patent application Ser. No. 572,466, filed Jan. 20, 1984. The acoustical panels described in the co-pending application generally involve the encapsulation of fiberglass along with one or more other materials in a durable plastic. These panels have proven to be durable and easily washable. They have also proven to be satisfactory from an acoustical standpoint. These panels achieve their acoustical performance through sound absorption and sound transmission.